<?php
$username = "Austin Leath -_#";
$username_err = "no error";
if(preg_match('/[^a-z_\-0-9]/i', $string)) {
  $username_err = "Username can only contain alphanumeric characters, dashes, and underscores.";
}

echo $username_err
?>

<?php
//generate 239 rgba colors for codecatch's 239 supported programming languages!
//this was used to generate the colors that are used in the pie chart on https://codecatch.net/graphs.php
function rgbagenerator() {
  $count = 239;
  for ($i=0; $i < $count; $i++) {
    echo "'rgba(". mt_rand(0,255) . ",". mt_rand(0,255) . ",". mt_rand(0,255) . ",1)',";
    echo "<br>";
  }
}

rgbagenerator();
?>

<?php
function getFileExtension($file) {
    return end(explode(".", $file));
}
?>

<?php
header('Content-Type:text/html');

$jsonData = json_decode(file_get_contents("names.json"));
$namesArray = array();

foreach($jsonData as $data) {
  $namesArray[] = $data;
}

for($i = 0; $i < 64000; $i++) {
  echo 'D.add_edge("'. $namesArray[array_rand($namesArray)] . '", "' . $namesArray[array_rand($namesArray)]. '")';
  echo "<br>";
}
?>

<?php
$im = imagecreatefrompng('example.png');
$size = min(imagesx($im), imagesy($im));
$im2 = imagecrop($im, ['x' => 0, 'y' => 0, 'width' => $size, 'height' => $size]);
if ($im2 !== FALSE) {
    imagepng($im2, 'example-cropped.png');
    imagedestroy($im2);
}
imagedestroy($im);
?>

<?php
   $json ='{"id":1,"name":"foo","interest":["wordpress","php"]}';
   $obj=json_decode($json);
   echo $obj->interest[1]; //prints php
?>